The present invention concerns methods and formulations for repelling insects, particularly for repelling mosquitoes and ticks.
Insect repellants are widely used throughout the United States and throughout the world. In some regions, the use of insect repellants is critical to avoiding or reducing the occurrence of disease carried by insects. For example the Centers for Disease Control (CDC) receives nearly 10,1000 reports of Lyme disease (transmitted by deer ticks) and 1,000 reports of encephalitis (transmitted by mosquitoes) annually).
Currently, the most common insect repellent is N,N-diethyl-meta-toluamide (DEET). DEET was designed to be applicable to the skin of subjects, and is designed to repel rather than kill insects. Although in use for some time, concern has recently emerged about the potential toxicity of DEET to children. Recently the US Environmental Protection Agency (EPA) determined that it would no longer allow child safety claims on labels for DEET-containing products.
The United States EPA Facts: Methyl Nonyl Ketone (July 1995) describes methyl nonyl ketone as a dog and cat repellent/training aid and iris borer deterrent, but does not suggest its use as an insect repellent.
U.S. Pat. No. 2,283,471 to Swaine describes the use of compounds such as methyl nonyl ketone and methyl undecyl ketone as contact insecticides for aphids and similar piercing-sucking insects (all primitive plant-feeding insects) which require contact insecticides for their control, but does not suggest their use as insect repellents.
R. Linderman et al., Pesticide Biochemistry and Physiology 35, 291-299 (1989), describes the inhibition of insect juvenile hormone esterase by xcex1,xcex2-unsaturated and xcex1-acetylenic trifluoromethyl ketones, but does not suggest the use thereof as insect repellents.
Accordingly, there remains a need for new ways to repel insects, particularly mosquitoes and ticks.
Accordingly, the present invention provides a method of repelling an insect pest, comprising applying to a subject or substrate, in an amount effect to repel the insect pest, a compound of Formula I: 
wherein R is C4-C20 linear or branched alkyl, preferably linear and preferably C7 to C13 alkyl.
Particularly preferred insects for application of the present method are mosquitoes, ticks and cockroaches.
In one preferred embodiment, the insect for application of the present method is a thrip.
In another embodiment, the insect for application of the present method is a biting fly such as a deer fly.
In another embodiment, the insect for application of the method of the present invention is a gnat.
In another embodiment, the insect for application of the method of the present invention is an aphid.
Further aspects of the present invention include compositions comprising compounds of Formula (I), or other active compounds, in combination with carriers or other ingredients for repelling insects, and the use of compounds of Formula (I) or active compounds disclosed herein for the preparation of a composition for repelling insects.